1. Field of the Invention
The present invention relates to a child seat in which a slope of a back portion is changed with a motion of a seat portion in a longitudinal direction.
2. Description of the Related Art
A child seat provided with a reclining mechanism for adjusting an angle of the back portion has been conventionally put to practical use. Various kinds of structures are proposed as the reclining mechanism. As one of them, there is proposed a reclining mechanism having a structure in which the rear end part of a seat portion is pivotally connected to the lower end part of a back portion, and the seat portion is provided so as to be movable in the longitudinal direction together with the lower end part of the back portion to thereby change the slope of the back portion.
In the child seat in which the seat portion and the back portion are interlocked as mentioned above, a restraint belt is once drawn out from a restraint position on the upper surface side of the seat portion (that is, a restraint position on a sitter side) to the rear side of the back portion with passing through the back portion, and is arranged in such a manner that the belt is closely attached to both of the back surface of the back portion and the lower surface of the seat portion and is restrained at a restraint position on the front end of the seat portion. Accordingly, when changing the angle of the back portion, a distance between the restraint positions with respect to the restraint belt is changed, and there is a possibility that the belt comes short and tends to be tightened with laying the back portion down. Also, the seat portion goes up in accordance with a forward movement of the seat portion due to a slope of a seat surface of a vehicle on which the child seat is placed, and a restraint condition for a sitter is changed according to that movement. Accordingly, there is a possibility that an impact resistance becomes unstable.
Accordingly, an object of the present invention is to provide a child seat which can inhibit a restraint condition from being changed in the case of changing a seat portion and a back portion in an interlocking manner.
In order to solve the above problem, according to one aspect of the present invention, there is provided a child seat comprising: a main body; a seat portion which is supported by the main body so as to be movable in a longitudinal direction; a back portion which is connected to the main body so as to be pivotally around an axis in a lateral direction and be movable within a predetermined range in a direction orthogonal to the axis, and which is pivotally connected to a rear end part of the seat portion on a lower end side thereof; a restraint belt which is drawn out to a rear side of the back portion from a restraint position on an upper surface side of the seat portion through the back portion, and which is extended to a restraint position on a front end part of the seat portion via a lower surface side of the seat portion; and a belt position regulating device for moving the restraint belt which is arranged around the rear end part of the seat portion backward from the back surface of the back portion.
According to the above aspect, since the restraint belt is backward apart from the pivotal center between the seat portion and the back portion, a required length of the restraint belt is reduced in the rear side of the back portion as the back portion is reclined. As a result, the short of the belt length at a time of reclining the back portion is compensated, and it is possible to inhibit the restraint condition of the belt from being changed as a whole, or it is possible to cancel the change of the restraint condition.
In the child seat according to the present invention, the main body may be provided with a belt holding device which is in contact with the restraint belt at a time when the seat portion moves forward to a predetermined position, and holds the restraint belt at a fixed position with respect to the main body regardless of a further forward movement of the seat portion. In this case, it is possible to limit the change in the belt length which is caused by the provision of the belt position regulating device to a proper range.
The belt position regulating device may be provided in the seat portion. In this case, there can be obtained an advantage that the position at which the belt position regulating device and the restraint belt are in contact with each other is not affected by the change in the slope of the back portion.
The seat portion may be supported to the main body via parallel link mechanism. In this case, even when the seat surface on which the main body is mounted is inclined obliquely, it is possible to longitudinally move the seat portion while keeping the height thereof constant. Accordingly, together with the effect of inhibiting the change of the belt length mentioned above, it is possible to securely inhibit the change of the restraint condition of the sitter and it is possible to stabilize the impact resistance without relation to the slope of the back portion.
The belt position regulating device may keep a position of the restraint belt in such a manner that a change of a length of the restraint belt required between the restraint position on the upper surface side of the seat portion and an insertion hole of the back portion through which the restraint belt passes is counterbalanced with a change of a length of the restraint belt between the insertion hole and a position at which the belt abuts the belt position regulating device regardless of a reclining motion of the back portion.
In the preferred embodiment of the present invention, the restraint belt is an assembly of a pair of shoulder belts and an adjust belt, one end of each shoulder belt is fixed to the seat portion while another end of each shoulder belt is connected to one end of the adjust belt on a rear side of the back portion, the adjust belt is arranged around the rear end part of the seat portion and is extended along a lower surface of the seat portion, and another end of the adjust belt is drawn out forward from the front end part of the seat portion via an adjuster which inhibits a backward returning motion of the adjust belt to thereby restrain the adjust belt. The belt position regulating device may be brought into contact with the adjust belt. The main body may be capable of being fixed to a seat of a vehicle by utilizing a harness of the vehicle.
According to another aspect of the present invention, there is provided a child seat comprising: a main body; a seat portion which is supported by the main body so as to be movable in a longitudinal direction; a back portion which is connected to the main body so as to be pivotable around an axis in a lateral direction and be movable within a predetermined range in a direction orthogonal to the axis, and which is pivotally connected to a rear end part of the seat portion on a lower end side thereof; a restraint belt which is drawn out to a rear side of the back portion from a restraint position on an upper surface side of the seat portion through the back portion, and which is extended to a restraint position on a front end part of the seat portion via a lower surface side of the seat portion; and a belt position regulating device which defines a path of the restraint belt so that the restraint belt drawn out to the rear side gradually goes backward from a virtual line obtained by connecting a connection position between the seat portion and the back portion and a restraint belt passing position of the back portion, as the restraint belt moves close to the lower end side of the back portion.
According to the above aspect, the restraint belt moves backward apart from the connection position between the seat portion and the back portion in the rear end part of the seat portion. Accordingly, in the same manner as the child seat mentioned above, the short in the length of the belt at a time of reclining the back portion is compensated, and the change in the restraint condition of the belt is inhibited as a whole or cancelled.
According to still another aspect of the present invention, there is provided a child seat comprising: a main body; a seat portion which is supported by the main body so as to be movable in a longitudinal direction; a back portion which is connected to the main body so as to be pivotable around an axis in a lateral direction and be movable within a predetermined range in a direction orthogonal to the axis, and which is pivotally connected to a rear end part of the seat portion on a lower end side thereof; and a restraint belt which is drawn out to a rear side of the back portion from a restraint position on an upper surface side of the seat portion through the back portion, and which is extended to a restraint position on a front end part of the seat portion via a lower surface side of the seat portion, and the seat portion is supported to the main body via a parallel link mechanism.
According to the above aspect, even when the seat surface on which the main body is mounted is inclined obliquely, it is possible to inhibit the restraint condition of the sitter from being changed by moving the seat portion longitudinally while keeping the height of the seat portion constant.